PROJECT SUMMARY This application to NHLBI Clinical Trial Pilot Studies describes a pilot clinical study to evaluate the combination of rosuvastatin with enoxaparin in order to prevent venous thrombosis following ovarian cancer surgery. Venous thromboembolism is a leading cause of preventable post-surgical mortality. Ovarian cancer patients are at a particularly high risk for thrombosis following surgery with rates that exceed 10% despite receiving recommended thromboprophylaxis. Rosuvastatin has been shown to prevent venous thrombosis but has not been prospectively evaluated in cancer patients. Elevated numbers of circulating procoagulant microparticles are associated with an increased risk of thrombosis in cancer patients and there is evidence that statins effectively decrease the generation of these procoagulant microparticles. We propose a pilot trial in women undergoing surgery for ovarian cancer where women will be randomized to receive enoxaparin alone or enoxaparin in combination with rosuvastatin for 60 days. The specific aims of this pilot study are focused on establishing reliable point estimates for the cumulative incidence of venous thromboembolism at day 60 following ovarian cancer surgery, evaluating trial feasibility, and optimizing recruitment across multiple sites. The correlative aims of the proposal focus on innovative approaches towards investigating the mechanistic, prognostic, and diagnostic significance of microparticles in ovarian cancer. Collectively, these data will enable the conduct of the first phase III clinical trial to evaluate the antithrombotic efficacy of a statin in a high risk cancer population.